Method of converting iron-sand into briquets or lumps.



UNITED STATES Patented May 3, 1904- PATENT OFFICE;

THOMAS ROUSE, OF STAMFORD HILL, ENGLAND, ASSIGNOR OF ONE- HALF TOHERRMANN COHN, OF LONDON, ENGLAND.

METHOD OF CONVERTING IRON-SAND INTO BRIQUETS OR LUIVIPS.

SPECIFICATION forming part of Letters Patent No. 758,853, dated May 3,1904.

Application filed October 27, 1903. Serial No. 178.7'75- (No specimens.)

T 0 [all whom, it 771/(07 concern:

Be it known that I, THOMAS ROUSE, a British subject, residing at 7 OldHill street, Stamford Hill, in the county of Middlesex, England, (whosepost-office address is 7 Old Hill street, Stamford Hill, London, N.,England,) have invented a new and useful improved method of convertinginto briquets or lumps iron-sand, whether natural or prepared, byreducing to powder iron ore or iron wastes, of which the following is aspecification.

I am aware that numerous attempts have been made to utilize iron-sands,powdered iron ore, powdered iron wastes-such as blue-billy, rich slags,and the likein the manufacture of iron and that patents have beengranted for various inventions in which such sands, ores, and wasteshave been mixed together and with other substances, such as lime,carbon, peat, and with various earths, minerals, and chemicals. Suchmixtures have been rendered plastic for molding by the use of tar, clay,sludge, mucilage, pyroligneous acid, and soap refuse. It has beenproposed to use the blocks thus prepared in their plastic condition inthe furnace or to harden them by exposure to the vapor of water at from196 to 212 Fahrenheit in a closed chamber from four to six days or tobake them at temperatures of from 372 to 932 Fahrenheit or to addsuflicient coal and by coking the mixture produce what has been termedan iron-coke or simply to let the lumps dry naturally in a dry place.

The object of this invention is to convert iron-sand concentrates intobriquets or lumps, whether the sand dealt with is a natural sand or oneartificially prepared by the reduction and concentration of iron ore oriron wastes or whether it be a mixture of such sands, and is moreespecially for effecting the conversion into briquets without theaddition of lime or any other substance than a soluble silicate orsilicates, preferably commercial water-glass, as a binding medium, sothat the briquets made of the sand where the latter is produced andconcentrated may contain the largest possible percentage of iron, with aview to the saving of freight and handling charges.

The sand is thoroughly mixed with a solution of about one measure ofcommercial water-glass in fifty measures of hot water. During theprocess of mixing the heat may, if necessary, be kept up and, further,watervapor added by injecting steam or by spraying with hot water and byheating the mixer in any suitable way. The quantity of the water-glasssolution must be such that when cooled the mixed mass is in astifi'plastic condition, although gritty, so that it can be molded by hand orby any suitable machine into briquets, which when pressed aresufficiently stable to be conveyed by a carrier-belt or upon plates orin any suitable way to a drying-chamber, in which they are hardened. Thehardening is effected by placing the molded lumps in a chamber throughwhich hot air and steam are passed. The atmosphere of the chamber mustbe kept uniformly hot and contain some water-vapor. The hot-air supplyand the steam-supply are kept under control by means of valves in suchway that the atmosphere of the chamber can be prevented from becomingfully saturated with vapor at atmospheric pressure. Condensation ofsteam in the chamber is thus prevented. The chamber may be constructedof brickwork, with doors or shutters which can be more or less opened toregulate the escape of hot air and steam, as may be desirable. Theobject is to secure a constant circulation of a mixture of hot air andsteam in and through the chamber without condensation of vapor therein.The air may be heated in any known way, and the current through thechamber may be caused by means of a blower or of a blast-fan or of anexhaust-fan, or a jet or jets of steam may be arranged to cause theinjection of air. The waste air and gas from a steam-boiler flue or froma blast or other furnace may be used in the chamber.

The employment of a mixture of hot air and steam in such way as toprevent the air becoming fully saturated with moisture causes the blocksof concentrated iron-sand moistened as aforesaid with water-glasssolution to harden in from one to ten hours, according to thetemperature maintained in the chamber being mixed. In such cases theblocks must remain longer in the hardening-chamber. Gonsiderably moresteam is used, and a temperature from about 200 to 350 Fahrenheit ispreferable. At this lower temperature the atmosphere of the-chamber maybe prevented from becoming fully saturated with vapor by superheatingthe steam before it is injected into the chamber.

What I claim as my invention, anddesire to secure by Letters Patent, is

The process of agglomerating by means of solution of waterglass andhardening into lumps or hard blocks, iron-sand, powdered iron ore orblue-billy or the like, or mixtures thereof, by means of a mixture ofhot air and steam at atmospheric pressure in a ventilated chamber, inwhich condensation of the steam into a deposit of water of condensationis prevented by regulating the supply of hot air and steam and theventilation; all as hereinbefore described.

In testimony whereof I have signed my name to this specification, inpresence of two subscribing witnesses, this 14th day of October,

THOMAS HOUSE. Witnesses:

THos. WILKINS, DAVID J. MOCKRIDGE.

